Each individual's genetic information recorded on genomic DNA is retained in the form of DNA. Such information is output via RNA as functional molecules such as proteins. Therefore, all genetic information may be regarded as having a chemical form, and at the same time, being an information medium. Although genetic information is not an electronic digital signal, a system for maintaining the security of that information is important when it comes to its safe maintenance.
Most organisms convert all the genetic information of each individual into a database and maintain that information within cells in chemical, molecular forms called genes. Genetic information is extracted from the database in the form of RNA anytime as needed, thus maintaining the activities supporting life. In multicellular organisms, every one of the cells constituting an individual, retains all the information of the whole individual in the form of genomic DNA. That is to say, an individual has as many copies of the database as the number of cells constituting the individual. Due to the presence of a great number of copies of information, maintaining the security poses an extremely difficult problem.
Among information retained in genomic DNA, there are many pieces of information requiring security. Currently, human genomic DNAs are being sequenced. The genetic information on genomic DNA naturally varies greatly between species, but there are also many slight differences even among individuals of the same species. Such differences are expressed as biological properties (phenotypes) of each individual. Phenotypes ranging from life span to a risk for contracting a specific disorder, and also as far as certain personalities, are said to be influenced by genomic DNA. Such genetic predispositions may have a great social significance in some cases, and hence, such information requires a high level of security. For example, personal information on a genetic predisposition of having a high risk of contracting a disease should not be easily accessible to a third party.
Gradual elucidation of the genome structure is expected to lead to an increase in genetic information analysis. As a result, genetic information requiring secure maintenance is likely to continue to rise. Therefore, a technique capable of preventing the analysis of genetic information recorded in genomic DNA is important.
There are many pieces of important information not only in genomic DNA information, but also in personal information that can be elucidated by analyzing biological samples. For example, it is generally prohibited by law to test whether an individual is infected by a specific virus without the consent of that individual. If such information is allowed to be readily made public, the individual is likely to undergo social discrimination regardless of his or her personality or will. Therefore, the provision of a technique capable of managing information derived from biological samples is useful.
Despite the essential necessity for a security system for actively preventing the leakage of such personal information encoded by DNA or RNA or in other chemical molecular forms, no effective means for that purpose is available yet. There are many techniques for maintaining the security of genetic information obtained by analyzing each individual's DNA or RNA that have already been converted into electronic digital signals. Such electronic information can be controlled by a centralized management using a computer. However, it is impossible to maintain the security of information recorded as chemical substances such as DNA by using management techniques for electronic information, because the information source is held in cells constituting individuals. A large number of gene copies exist in a single individual, and, moreover, blood cells, mucous cells and the like can be readily collected. Furthermore, since techniques for culturing these harvested cells and amplifying genes are available, it may be impossible to maintain the information security on a cell unit level.
As a result, at present, information security is barely maintained solely by the rule or morale that tests are not to be conducted without a person's consent. Therefore, it is an important objective to provide a technique capable of more securely maintaining the security of such information that can be obtained from a living organism. Nowadays, when the genomic draft has already been revealed and the post-sequencing era is coming around the corner, the protection of genetic information is likely to become an extremely important issue.